This invention relates to a device for the variation of the setting of an angling blade of earthmoving machinery on swivelling or tilting with the aid of hydraulically operated piston/cylinder units arranged to pairs. In normal practice the movement of angling blades is effected by a pair of piston/cylinder units arranged one on the left and one on the right, whereby the cylinders are pressurized simultaneously and in opposed sense. A drawback of such a system is that the piston/cylinder units operate at different speeds depending on the back pressure against the blade on the relevant side. This drawback can only be eliminated by means of so-called flow dividers and additional hydraulic components. A further difficulty to be contended with is in the occurrence of oil losses through leakages in pistons and cylinders which are not compensated and cause the tilting thrust to drop so that in limiting cases no cylinder movement and hence no tilting movement is possible.
The invention has therefore the object of eliminating these shortcomings and of providing a device which allows at any time proper swivelling and tilting in the simplest fashion and with simple means.